Purification and characterization of a thermostable, haloalkaliphilic extracellular serine protease from the extreme halophilic archaeon Halogeometricum borinquense strain TSS101

Abstract

A novel haloalkaliphilic, thermostable serine protease was purified from the extreme halophilic archaeon, Halogeometricum borinquense strain TSS101. The protease was isolated from a stationary phase culture, purified 116-fold with 18% yield and characterized biochemically. The molecular mass of the purified enzyme was estimated to be 86 kDa. The enzyme showed the highest activity at 60 degrees C and pH 10.0 in 20% NaCl. The enzyme had high activity over the pH range from 6.0 to 10.0. Enzymatic activity was strongly inhibited by 1 mM phenyl methylsulfonyl fluoride, but activity was increased 59% by 0.1% cetyltrimethylammonium bromide. The enzyme exhibited relatively high thermal stability, retaining 80% of its activity after 1 h at 90 degrees C. Thermostability increased in the presence of Ca2+. The stability of the enzyme was maintained in 10% sucrose and in the absence of NaCl.

Production and some properties of crude alkaline proteases of indigenous Central Amazonian rhizobia strains

“…At present, Bacillus (Gupta et al, 2002;Nilegaonkar et al, 2007), Pseudomonas (Ogino et al, 2001;Rahman et al, 2005), Aspergillus (Tunga et al, 2003), Streptomyces (Azeredo et al, 2004) and Penicillium (Agrawal et al, 2004) species are considered to be the most important sources of industrial proteases. Nevertheless, various other sources of microbial proteases are being investigated (Elibol and Moreira, 2005;Seeta Laxman et al, 2005;Vidyasagar et al, 2006). While alkaline proteases from several bacteria have been extensively characterized, similar attention has not been paid to rhizobia bacteria.…”

Isolation and characterization of a haloalkaliphilic protease producer bacterium from Wadi Natrun in Egypt

“…Raising the incubation temperature to 40°C increased the specific proteolytic activity up to 357 TU/mg protein. Medium formula Denizci et al, 2004;Vidyasagar et al, 2006). Nutritional regulation studies on the expression of alkaline protease in NA7 were carried out by applying a 2-level Plackett-Burman multi-factorial experiment (Plackett and Burman, 1946).…”

Pengaruh Garam Monovalen (NaCl dan KCl) dan Divalen (CaCl2 dan MgCl2) Terhadap Aktivitas Protease Ekstraseluler Bakteri Halofilik Isolat Bittern Tambak Garam Madura

“…Selain itu, adanya kation juga dapat memberikan efek perlindungan (shielding effect) protein terhadap pengaruh kondisi lingkungannya [1]. Pada konsentrasi garam NaCl (3,4 M), CaCl2 (100 mM) dan MgCl2 (1mM) dapat meningkatkan aktivitas protease serin ekstraseluler dari bakteri Halogeometricum borinquense strain TSS101 sebesar 100%, 121%, dan 62% [8]. Kation [8].…”

“…Pada konsentrasi garam NaCl (3,4 M), CaCl2 (100 mM) dan MgCl2 (1mM) dapat meningkatkan aktivitas protease serin ekstraseluler dari bakteri Halogeometricum borinquense strain TSS101 sebesar 100%, 121%, dan 62% [8]. Kation [8]. Pada umumnya ion-ion ditambahkan dalam bentuk garamnya.…”

“…Berdasarkan terdahulu diketahui bahwa kestabilan enzim bakteri halofilik dipengaruhi oleh jenis dan konsentrasi garamnya [1,8]. Sehingga dalam penelitian ini perlu dilakukan penentuan pengaruh jenis garam yaitu garam monovalen (NaCl dan KCl) dan divalen (CaCl2 dan MgCl2) terhadap aktivitas dan profil aktivitas protease ekstraseluler bakteri halofilik isolat bittern tambak garam Madura.…”